OCZ Agility 4 (256GB) Review
 

For the last few years, OCZ's consumer SSD lineup has primarily consisted of two models: Vertex and Agility. The history of these two goes all the way back to 2009 when OCZ realized that they can differentiate their SSDs by equipping them with different quality NAND. In first and second generation Vertex and Agility SSDs, the difference between the NAND was the manufacturer and process node. First generation Vertex used strictly Samsung NAND, whereas Agility opened the doors of cheaper prices by using Intel and Toshiba NAND. Back then, Samsung was in control of the SSD and NAND market, which allowed them to price themselves higher than others. With second generation Vertex and Agility, OCZ switched to SandForce's SF-1221 controller and Vertex 2 used Micron NAND, while Agility 2 used Intel NAND.

http://www.anandtech.com/show/6143/o...4-256gb-review